Altimetric determining device



x2 2,294,411 SEARCH ROOM CROSS REFERENCE.

Se t. 1, 1942. D. E. MORRISON E fi ALTIMETRIC DETERMINING DEVICE Filed-Apri1 9, 1941 a Sheets-Sheet 1 INVENTOR B011 1115 E. Murritsnn BY {hala ,45 tZS/YGLML ATTORHEYS Sept. 1, 1942. n. E. MORRISON 2,294,417

ALTIMETRIC DETERMINING DEVICE Filed April 9, 1941 s Sheets-Sheet 2 Ffgfi- 1 v 25- ll:

v 26417! o M INVENTOR Dmu 11:15 E- Morris on ATTORNEY H? .P b b h .r .P L J 7 w 5 ZZZD 1* L Mil, M w Q 3 h R w {J S 4 00 am E 2, b 15 MM M 2 m 4 E O 5 ll T m 4 mE M s :9. a a 3 Q 3 m E w w w w 3 G F M Ma m D 1 w G Mn m m 1 P E N u m T. 9 1 m m m m m E D .A .I E N F. D m m P2 I m w, a a w w w w w; w w m w 6 .w L w a y 7 1 5/ w ug 7 a .4 v n x 1 i a Patented Sept. 1, 1942 mar m ALTEMETRIC DETERMINlNG DEVICE Douglas E. Morrison, United States Army, Trenton, Ga.

Application April 9, 1941, Serial N0. 387,659 7 Glaims. (Cl. 33-66) me of any royalty thereon.

This invention relates to an altimetric determining device for constantly determining the altitudes of aerial targets.

A. principal object of the invention is to pro-.

vide a rugged, simple, flexible altimetric device adapted for quantity production at low cost.

A further object of the invention is to provide an altimetric device especially useful for determining the altitude of fast moving low flying aircraft adapted for use with a relatively short base.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a diagrammatic View showing the manner in which the a-ltimetric device of this invention is disposed with respect to a firing battery;

Fig. 2 is a side elevation of a hydraulic altimeter base end instrument constituting one of s the instruments of the device f this invention;

Fig. 3 is a sectional view taken upon the line 3-3 of Fig 2;

Fig. 4 is a plan view of the instrument shown in Fig. 2

Fig. 5 is a front elevation of the hydraulic altitude plotting instrument of this invention with struments A1, A2, and A3 are arranged in the form of a triangle about the battery G at known distances apart and are used to measure the angular heights of a target in the plane of a base line constituting one of the sides of the triangle and transmit the same by suitable means, herein shown as hydraulic transmission lines, to a plotting instrument B where altitude is graphically and continuously determined and transmittcd to another or other fire control instruments as required, such as the data computer P as shown in Fig. 1 of my copending application, Serial No. 387,657 filed April 9, 1941.

Each of the altimeter base end instruments A1, A2, A3, etc. are identical in construction and comprise a suitable support such as a tripod 10 which may be provided with leveling devices H to level the head l2 thereof.

A vertically disposed shaft [3 is rotatably mounted in the tripod head 17. in any suitable manner and may be locked against rotation as by means of the set screw 14. At the upper end portion of shaft [3, a second shaft i5 is suitably journaled thereon as by means of a diametral bore It formed in the shaft 13 rotatably receiving the shaft 15. On one side of shaft it a pinion !1 is affixed to the shaft 15 for rotation therewith, and to the other side of shaft l3 a transverse pin it is aiiixed to the shaft [5. The pin I8 has a Y-shaped bracket is mounted thereon for rotation about the axis of the pin in-such manner as to clear the adjacent end of shaft l5. A shoulder rest 26 is fixed to the bracket l9 as clearly shown in Fig. 2 and carries opposed rear sights 2 l, 22. Front sights 23, 26 for use with the rear sights 2|, 22, respectively, are mounted upon opposed end portions of the pin H3 or bracket l9, as may be desired,

A cylinder is demountably secured to the shaft l3 in parallelism therewith, as by means of the clamps 2B and has provision at its lower open end to removably receive in fluid-sealed relation one end of a flexible conduit F1, F2, F3, etc, according to the base end instrument to which such cable is secured. A piston 28 is disposed within the cylinder and is provided with an obturator cup 29 at its lower end to prevent the escape of fluid from chamber 39 upwardly past the piston. A rack bar is secured to the upper end of the piston 28 and disposed in engagement with the pinion l! whereby rotation of the shaft 15 and pinion ll will effect translation of the rack bar 3! and piston 28 in the cylinder 25. An azimuth plate 32 is secured to the tripod head [2 and carries adjustable clamps 3-3 between which a pin 34 fixed to the shaft l3 may move.

The altitude plotting instrument B comprises a base of any desired character which for convenience is herein shown to be a rectangular frame 36 supported by legs 31 at its corners.

Secured to the supporting base are receivers R1,

R2, R3, etc" corresponding to the base end instruments A1, A1, A3, etc. Each of the receivers are identical in construction and comprise a cylinder 39 provided with a piston 46 and obturator cup M secured to a rack bar 12. The receivers R1 and R2 are mounted upon supports 43 which are adjustable to and from each other on the front side element 44 of the frame 36 and may be retained in adjusted position by clamps 65. The supports 43 are each provided with brackets 45 within which pinions 41 are journaled in meshing relation with the rack bars 42. A plotting arm P1 is secured to the pinion 47 of receiver R1 through the axle therefor while similarly a plotting arm P2 is secured to the pinion 41 of receiver R2 in like manner. The receiver R3 is mounted intermediate the ends and transversely of the rear side element 48 of the frame 38 with its forward end portion supported by an intermediate frame member 49. The forward end of the support for receiver R3 has a pinion 50 mounted thereon upon a shaft i extending to either side in parallelism with the sides of the frame and racks 42 of receivers R1, R2. Mounted upon the shaft 5| on either side of the pinion 5G is a bevel or other suitable gear 52 adapted to be slidably moved upon the shaft and retained in desired position by set screws 53. Assembly frames 54 are slidably mounted upon the shaft 5! about each of the gears 52 and have gears 55 therein intermeshing with the gears 52. The gears 55 have their axes of rotation in planes parallel to the planes containing the axes of rotation of pinions 4i and the assembly frames are supported upon the member 49 in such manner as to dispose the axes of the pinions 55 in the horizontal plane. As clearly shown in Fig. 6, the assembly frames are held in position upon the shaft. 5! by the gears 52 and set screws 53. Plotting arms P3, P4 are secured to the ears 55, respectively, in parallel relation to each other and in a plane parallel to the plane containing arms P1, P2. The conduits F1, F2, F3, etc. are secured to the cylinders 39 of the receivers R1, R2 and R3 in fluid-sealed relation and to maintain a back pressure in the conduits when charged with fluid, the pinions M, 52 are biased to move the pistons -18 toward normal positions adjacent the entrance ends of the cylinders as by means of weights W suspended from cables attached to the shafts of pins 6?, 59 or suitable springs for such purpose. Replenishing reservoirs 55 similar to the device disclosed in Fig. 6 of the transmission system of my co-pending application Serial No. 387,658 filed April 9, 1941, for the purpose of keeping a constant volume of fiuid in each of the conduits F1, F2, F3, etc. and associated trans mitter and receiver cylinders are provided as indicated in Fig. 1.

A grid of any suitable construction is placed in the vertical plane between the plotting arms P3, Pr. and P1, P2. Conveniently the grid may be formed of a series of vertically spaced parallel wires 5? spaced to a scale adapted to the purpose and identified by tabs 58 numbered to correspond to the altitude that the given wire represents. By this construction, intersections of the plottin arms P1, P2 etc. may be viewed against the grid from either side thereof.

In operation the base end instrument cylinders 25, conduits F1, F2, F3 etc. and altitude instrument receiver cylinders 39 will be filled with fluid through the replenishing reservoirs 55. The base end instruments A1, A2, A3. etc. will each be orientecl by first arranging the shoulder rest 20 in parallelism with the face of pinion IT, in which position it may be held as by inserting a pin 59 through properly aligned holes in the shaft is and pin l8. Next the sights of a particular base end instrument, for example instrument Ai, will be aligned upon one of the other instruments with which it is arranged to cooperate, for example, instrument A2 and a clamp 33 clamped in abutting relation with the pin 34 to prevent counterclockwise movement of the sights out of alignment with instrument A2 as viewed in Fig. l. The sights of instrument A1 are next trained upon the other instrument A3 in the system with which it is arranged to cooperate and the other clamp 33 locked in abutting relation with pin 34 to. prevent clockwise movement of the sights away from alignment with instrument A3 as viewed in Fig. l. A similar procedure is followed in orienting the other instrumenm A2, A3 of the system after which the pins 59 are removed. The instruments A1, A2, A3 are now conditioned for service with the pin 34 of each instrument located between the clamps 33 thereof and the clamps arranged to abut the pin 34 to position the sights in the plane of one of the base lines A1A2, A2A3, or AsA1 as the case may be. When a target is designated, the base line to be used will also be indicated which for the purpose of further illustration will herein be selected as A1-A3. Upon indication of base line Al-AIl as the base line to be employed, as by suitable prearranged signal or a communication system, the

base end instrument operators A3, A1 will swing their instruments to a position where the pins 3 will abut the clamps 33 in such manner that the sights thereof will be disposed in the plane of base line A3A1, in which position the shafts will be locked by the set screws i l. The base end instrument operators A1, A3 then track the target by aligning the sights 2 l, 23 or 22, 24, as the case may be, upon the target. Component movement of the sights in the plane of the base line'A3A1 will be transmitted through rotation of the pinions i'i, racks 3i, pistons 28, fiuid in conduits F1, F3, pistons ii], racks 62 and pinions 41, 50, shaft 5i, gears 52!, to the plotting arms P1, P3 to cause the latter to intersect before the grid in scale relation to the vertical projection of the angular heights of the target upon the vertical plane containing the base line A3-A1 as observed from the stations of instruments A3, A1. It will be understood that during the orientation process, the axes of rotation of the plotting arms P1, P2, P3, P4 were positioned apart upon the altitude instrument to scale in conformity with the base line distances A1A2, A2-A3 and A3Al, respectively, The intersection of plotting arms P1, P3 may be read in terms of altitude from the grid and transmitted by any suitable means to a position where required. It is of course obvious that the receiver A3 must have the two plotting arms P3, P4 in order to get intersections with either of the plotting arms P1, P2 where only one receiver is employed as indicated.

The base end instruments are capable of measuring and transmitting angles from 0 to 180 by the simple expedient of changing from sights 2!, 23 to 22, 2-4 or vice versa as the target passes the zenith. In order to prevent transmitting angles in error t the altitude instrument, the stock may be appropriately marked to indicate the side that is to always be held next to the face of pinion ll,

Operation of the other base end instruments on the other base lines will be in a manner similar to that above described in connection with base end instruments A1, A3.

Having now described a present preferred embodiment of the present invention, I claim:

1. In an altimetric determining system a base vertically disposed rotatable shaft, a second shaft rotatably mounted on said first named shaft for movement about an axis normal t said first shaft, a pin fixed to said last named shaft transversely thereof, a sighting system attached to said pin for rotation about the axis thereof, a cylinder fixed to the first shaft, a piston mounted in the cylinder, a rack bar secured to the piston, and a pinion secured to the second shaft in intermeshing relation with the rack bar.

3. The structure of claim 2 wherein said sighting system comprises a shoulder rest secured to said pin for rotation about the axis thereof and opposed front and rear sights mounted upon opposed portions of said pin and shoulder rest.

4. In an altimetric determining system and altitude instrument comprising in combination, a base, a pair of receivers adjustably mounted upon said base, a plotting arm mounted on each of said receivers for rotation thereby about parallel axes into intersecting relation relative to each other, a third receiver mounted on said base, a pair of spaced parallel arms mounted to be controlled by said third receiver, and means controlled by said third receiver and connecting said spaced arms for synchronous rotation in a plane parallel to the plane of said first arms into intersecting relation with the latter.

5. In an altimetric determining system an altitude instrument comprising in combination a base, a pair of cylinders adjustably secured to said base in spaced relation, pistons mounted in said cylinders, racks secured to the pistons, pinions mounted on parallel axes intermeshing with said racks, a plotting arm secured to each pinion for rotation about the axisthereof into intersecting relation, a third receiver mounted on the base provided wi h a piston and rack, a pinion mounted in intermeshing relation with the rack, a shaft secured to the pinion and extending to either side thereof, gears adjustably mounted upon either end portion of the shaft, assembly frames mounted on the shaft and retained in position of said gears, additional gears mounted in said assembly frames in intermeshing relation with said first named ears for rotation about axes parallel to the axis of rotation of said plotting arms, a plotting arm secured to each of said last named gears for rotation in parallel relation and into intersecting relation with said first named plotting arms, and means for connecting hydraulic conduits to all of said cylinders.

6. The structure of claim 5 in combination with means for creating a back pressure upon a fluid in said conduits.

7. The structure of claim 5 in combination with a grid interposed between said first and last named plotting arms,

DOUGLAS E. MORRISON. 

